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-   OpenFOAM Native Meshers: snappyHexMesh and Others (http://www.cfd-online.com/Forums/openfoam-meshing-snappyhexmesh/)
-   -   someLine.eMesh format file (http://www.cfd-online.com/Forums/openfoam-meshing-snappyhexmesh/72148-someline-emesh-format-file.html)

elisenda January 27, 2010 06:32

someLine.eMesh format file
 
Dear all,

I am trying to mesh an stl geometry with snappyHexMesh. I can see that the feature lines (or edges) I have in the geometry are omitted. The mesh don't follows the lines.

I would like to use the someLine.eMesh file but I don't know their format and I don't know where I have to place it into the structure directories.

I don't know if this is a good way but I have not other ideas.

1) Can anybody help me how to use and how to generate the someLine.eMesh file?
2) Have anybody any other ideas?

Thanks in advance,
Elisenda

Wolle January 27, 2010 10:57

Hi Elisenda,

Is that what you mean by "feature lines/edges are omitted"?

http://www.cfd-online.com/Forums/ope...try-edges.html

There are some other threads about that in the forum, but I (not experienced at all!) think, there's no solution to that problem at the moment.

I don't know, whether the someLine.eMesh approach is adequate for this kind of problem, but would be interested too. Anyway I didn't read anything about that yet and came across these settings just today...

Cheers
Wolle

elisenda January 28, 2010 03:52

Hello Wolle,

This is exactly what I mean.
I think the eMesh file can help me. I am not sure but I would like to try.
The problem is that I don't know their format.

Has anybody idea about the eMesh format?

norman1981 January 28, 2010 04:25

Quote:

Originally Posted by elisenda (Post 244019)
Has anybody idea about the eMesh format?

Hi!
Look at the iglooWithFridges/constant/triSurface/fridgeA.eMesh file:

/*---------------------------------------------------------------------------*\
| ========= | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox |
| \\ / O peration | Version: 1.6 |
| \\ / A nd | Web: http://www.openfoam.org |
| \\/ M anipulation | |
\*---------------------------------------------------------------------------*/

FoamFile
{
version 2.0;
format ascii;

root "..";
case "cavity";
instance ""constant"";
local "polyMesh";

class featureEdgeMesh;
object points;
}

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

// Points
(
(1.99 1.99 0.01) //0
(3.01 1.99 0.01) //1
(3.01 3.01 0.01) //2
(1.99 3.01 0.01) //3

(1.99 1.99 2.01) //4
(3.01 1.99 2.01) //5
(3.01 3.01 2.01) //6
(1.99 3.01 2.01) //7
)
// Edges
(
(0 1)
(1 2)
(2 3)
(3 0)

(4 5)
(5 6)
(6 7)
(7 4)

(0 4)
(1 5)
(2 6)
(3 7)
)
// ************************************************** *********************** //

Regards

Norman

elisenda January 28, 2010 05:30

Hi Norman,

Thank you for your very quick answer. I will try with this format.
I will say you if the mesh follows the edges.

Thanks and regards,
Elisenda

elisenda January 28, 2010 06:26

Hi Norman,

I used this format and the snappyHexMesh runs well. The problem is that the mesh don't follows the edges.
I don't know what I can do.

Any suggestions? :o
Elisenda

norman1981 January 28, 2010 06:29

Quote:

Originally Posted by elisenda (Post 244028)
Hi Norman,

Thank you for your very quick answer. I will try with this format.
I will say you if the mesh follows the edges.

Thanks and regards,
Elisenda

You're welcome!
I tried that solution last april and it didn't improve my case so much.. maybe the new snappyHexMesh version works better using these feature lines but I think you'll only get a refinement around your feature lines because the edge capturing is not already implemented in snappyHexMesh :-(
Anyway let me know!

Regards
Norman

elisenda January 28, 2010 08:09

Hi Norman,
I use "level 10" on the edges.eMesh file:

features
(
{
file "edges.eMesh";
level 10;
}
);


and the mesh is refined near the edges. I have a lot of elements. It is not bad, but it would be better follows the edges but without increase the number of elements. It is a pity. :(

Elisenda

norman1981 January 28, 2010 08:41

Hi Elisenda,

I agree but this is the only way to get a grid that follow in some way your edges because at this moment the edge capturing is not implemented in snappyHexMesh.

Norman

openfoam_user March 3, 2010 04:33

Hi Elisenda,

Have you find a way or a 'best strategy' to improve your mesh quality near the edges ?

Best regards,

Stephane

elisenda March 19, 2010 07:04

Stephane,

This is the only way I have found. I don't know if there is another one.


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